Quick connect retainer having tolerance for wide band of male tube dimensions

ABSTRACT

A connector for receiving a tube end having at least one radially enlarged upset. The connector comprises a hollow female connector body and a retainer disposed in the connector body. The retainer has an annular inner base ring defining a cylindrical surface to receive the tube end. The retainer further defines compressive members. The base ring has a limit surface facing the compressive members and a chamfer intersecting the limit surface and the cylindrical surface. The compressive members define an inner diameter and a space between the limit surface and the compressive members for securing the radially enlarged upset in the connector body. The inner diameter of the compressive members is at least as large as the diameter of the intersection of the chamfer with the limit surface.

This application is a continuation-in-part of copending application Ser. No. 09/151,480 filed on Sep. 10, 1998, which is a continuation of Ser. No. 08/673,574 filed on Jul. 1, 1996.

BACKGROUND OF THE INVENTION

This invention relates to fluid line systems which include quick connector couplings, and more particularly to a retainer for a quick connector coupling having tolerance for a wide band of male tube dimensions.

In automotive and other fields, quick connector couplings, which generally include a male tube received and sealingly retained in a female connector body, are often utilized to provide a fluid connection between two components or conduits, thus establishing a fluid line between the two components. Use of quick connector couplings is advantageous in that a sealed and secured fluid line connection may be established quickly and easily.

A number of methods and mechanisms exist for securing the male tube and female connector body of a quick connector coupling together. One retention mechanism, which is the subject of the present invention, involves use of a plastic retainer disposed within the connector body.

The retainer has a base ring disposed inside of the connector body which is connected to outer portions aligned with, and positioned inside of, the connector body entrance. Compressive members extend from the outer portions to positions spaced from the base ring. The outer ends of the compressive members abut a radial shoulder formed within the connector body to secure the retainer inside of the connector body, and an enlarged upset formed on the inserted male tube is captured in the space between the compressive members and base ring to secure the tube in the connector body.

Conventional retainer designs can tolerate only a narrow band of male tube dimensions. Introduction of new materials, suppliers and manufacturing methods, however, have led to use of male tubes having a broad and varying band of dimensions. Conventional retainers are often not able to accommodate tubes of varying dimensions. Consequently, different sizes of retainers must often be utilized for tubes having just minor differences in dimension. Significant expense results, since a new mold must be constructed for each retainer variation. Management, tracking and identification of multiple retainer variations for multiple customers also adds to complexity and expense.

The present invention addresses this problem by providing an improved retainer design which can tolerate a wider band of male tube dimensions.

SUMMARY OF THE INVENTION

The present invention is directed toward a connector for receiving a tube end having at least one radially enlarged upset. The connector comprises a hollow female connector body and a retainer disposed in the connector body. The retainer has an annular inner base ring defining a cylindrical surface to receive the tube end. The retainer further defines compressive members. The base ring has a limit surface facing the compressive members and a chamfer intersecting the limit surface and the cylindrical surface. The compressive members define an inner diameter and a space between the limit surface and the compressive members for securing the radially enlarged upset in the connector body. The inner diameter of the compressive members is at least as large as the diameter of the intersection of the chamfer with the limit surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a prior art quick connector coupling;

FIG. 2 is a partial sectional view of another prior art quick connector coupling;

FIG. 3 is an enlarged partial sectional view of a male tube captured by a retainer;

FIG. 4 is an enlarged partial sectional view of another male tube captured by a retainer;

FIG. 5 is a perspective view of the type of retainer of the present invention;

FIG. 6 is an enlarged partial sectional view of a male tube captured by a retainer according to the present invention;

FIG. 7 is an enlarged partial sectional view of another male tube captured by a retainer according to the present invention;

FIG. 8 is a sectional view of a set of mold dies and mold core pin for forming a retainer with the compressive members having an inner diameter approximately as large as the diameter of the intersection of the chamfer with the limit surface;

FIG. 9 is a sectional view of the set of mold dies and mold core pin of FIG. 8 after injection of plastic material into cavities defined in the set of mold dies and mold core pin;

FIG. 10 is a sectional view of the set of mold dies and mold core pin of FIG. 9 with the core pin being removed from the mold dies;

FIG. 11 is a sectional view of the mold dies of FIG. 10 with the mold dies being removed from the resultant retainer; and

FIG. 12 is a sectional view of an alternative set of mold dies and mold core pin for forming a retainer with compressive members having an inner diameter larger than the diameter of the intersection of the chamfer with the limit surface.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A prior art quick connector coupling 10 is illustrated in FIG. 1. Coupling 10 is comprised of a generally cylindrical female connector body 12 and a male tube 14. Connector body 12, in use, is connected to flexible hose or another system component. Likewise, male tube 14 forms a part of a fluid line system. Connector body 12 and tube 14 are connectable to form a permanent, but severable, joint in the fluid line.

Tube 14 includes a radially enlarged upset 16 formed a given distance from tube end 18. Upset 16 defines an abutment wall 20 formed perpendicular to the outside surface of tube 14 facing away from tube end 18, and a sloped wall 22 facing tube end 18.

A plastic retainer 24 is disposed within connector body 12. Retainer 24 is comprised of base ring 26, outer portions 28 and compressive members 30 extending from outer portions 28 toward base ring 26. Connecting leg portions 32 join base ring 26 and outer portions 28. The coupling illustrated in FIG. 1 also includes an indicator member 34 receivable in an indicator pocket 36. The indicator features are not part of the present invention but are explained in detail in U.S. Pat. No. 5,499,848.

Compressive members 30 each include at one end, a first locking surface 38 facing away from base ring 26, and at an opposite end, a second locking surface 40 facing base ring 26. First locking surfaces 38 abut a shoulder 42 formed in connector body 12 to secure retainer 24 inside of connector body 12, and second locking surfaces 40 abut abutment wall 20 of upset 16 to capture upset 16 in the space between compressive members 30 and base ring 26, and thereby secure male tube 14 in connector body 12. Compressive members 30 may be spread apart to permit insertion of tube 14 into connector body 12 to a secured position (illustrated), and conversely, to permit release of tube 14 (with use of an appropriate release tool).

Base ring 26 includes a central opening, defined by cylindrical wall 44, through which tube 14 passes and fits closely. A limit surface 46 is perpendicular to cylindrical wall 44 and, together with locking surfaces 40 of compressive members 30, defines the space within which upset 16 is captured. As is evident in FIG. 1, contact between sloped surface 22 of upset 16 and limit surface 46 of base ring 26 limits movement of upset 16 within this space. Conical flange 48 is formed on base ring 26 opposite limit surface 46. If retainer 24 and tube 14 are pressed further into connector body 12, conical flange 48 fits into conical cavity 50 of spacer 52 which is press-fit into connector body 12.

FIG. 2 illustrates a similar prior art coupling 60. Coupling 60 includes a connector body 62, a male tube 64 and a retainer 66. An O-ring seal 68 is held in connector body 62 by a spacer 70, and a hose 72 is received over the end of connector body 62. Retainer 66 is of the same type as the retainer shown in FIG. 1. It includes a base ring 74 and outer portions 76 joined to base ring 74 by connective leg portions (not shown) similar to leg portions 32 of FIG. 1. Compressive members 78 extend from outer portions 76 toward base ring 74. First locking surfaces 80 of compressive members 78 abut shoulder 82 to secure retainer 66 in connector body 62, and second locking surfaces 84 abut upset 86 formed on tube 64 to secure tube 64 in connector body 62.

Upset 86 differs from upset 16 of FIG. 1. It defines two abutment walls 88, each of which is substantially perpendicular to the outer surface of tube 64. Moreover, upset 86 is in an extremely tight fit in the space between compressive member locking surfaces 84 and perpendicular limit surface 90 of base ring 74. It has no range of movement within its captured space.

FIGS. 1 and 2 have been included and described herein because they are exemplary of retainer design and tolerance concerns relative to male tubes. Retainer 24 of FIG. 1 could accept a male tube having a slightly wider upset or with abutment walls of slightly different slope. Retainer 66 of FIG. 2, by contrast, is at its maximum tolerance. Upset 86 could not be widened, nor could any slope or radii be added to its abutment walls 88. FIGS. 1 and 2 also illustrate that male tube dimensions and configurations, particularly regarding the upsets, are not uniform. A tube having an upset of the same nominal width as upset 86 in FIG. 2, but having a sloped wall or radii similar to wall 22 of upset 16 in FIG. 1, would not fit properly within retainer 66 of FIG. 2. A retainer having a greater spacing between the base ring and compressive members would be required.

This problem is magnified in FIGS. 3 and 4. FIG. 3 depicts an upset 100 of a tube 102 captured by a retainer 104. The remaining details of the coupling, which 142 formed on male tube 144. Base ring 132 has a central opening defined by cylindrical surface 146, and a limit surface 148 facing compressive members 136 and perpendicular to cylindrical surface 146.

Base ring 132 and compressive members 136 are modified to provide tolerance for an expanded band of male tube dimensions. A chamfer 150 is formed between limit surface 148 and cylindrical surface 146 to provide the ability to accommodate sloped surfaces on upsets. Chamfer 150 is formed during the injection molding process by enlarging the outer diameter of the mold core pin and providing the core pin with a conical tip. A base ring formed without a chamfer, as depicted in phantom lines, could not accommodate upset 142.

Inner diameter portions 152 of compressive members 136, shown in phantom lines, are also removed as a result of use of an enlarged diameter mold core pin. Enlarging the diameter of the mold core pin to provide a chamfer on the base ring had not been considered a viable option before the present invention because, as shown, it results in increased spacing between the compressive members. Contact between the compressive members and the external (non-upset portions) surface of the male tube is lost. Applicant has found that this loss of contact does not significantly reduce the strength of the retainer. Moreover, as seen particularly in FIG. 7, enlargement of the compressive member inner diameter provides further increased tolerance for male tubes of varying dimensions. Furthermore, FIGS. 6 and 7 depict compressive members having inner diameters 20 approximately as large as the diameter of the intersection of the chamfer with the limit surface.

The retainer of the present invention is molded as follows and as illustrated in FIGS. 8-11. FIG. 8 illustrated a sectional view of a set 200 of mold dies 202 and mold correspond in function to the couplings of FIGS. 1 and 2, are not illustrated. Upset 100 is held in the space between compressive member locking wall 106 and base ring limit wall 108. Upset 100 includes abutment walls 110 which are substantially perpendicular to the outside surface of tube 102. Sloping wall portions 112 join walls 102 with the tube surface. Though the width of upset 100 is significantly less than the spacing between retainer walls 106 and 108, wall portions 112 cause contact between the upset and retainer base ring and compressive members, effectively pushing retainer 104 to the limit of its tolerance.

In FIG. 4, the retainer 104 of FIG. 3 is utilized, but a tube 120 having an upset 122 of different dimensions is introduced. Upset 122 is slightly wider than upset 100 of FIG. 3, and includes a more pronounced sloping wall portion 124. The result is that upset 122 does not fit properly in the space between retainer surfaces 106 and 108. Corner portions 126 and 128 of, respectively, the retainer base ring and compressive members, impinge on the upset. Hence, a slight change in the dimensions of the male tube has rendered retainer 104 ineffective.

FIG. 5 is a perspective view of the type of retainer of the present invention. The present invention, shown in FIGS. 6 and 7, provides a retainer design having tolerance for a wider band of tube dimensions. Retainer 130 of FIG. 6 is formed of injection molded plastic and has a base ring 132, outer portions 134 and compressive members 136 (one is shown). Outer portions 134 are connected to base ring 132 by connective leg portions (not shown) similar to leg portions 32 of the retainer of FIG. 1. First locking surface 138 of compressive member 136 abuts a shoulder of the connector body (not shown) to secure the retainer in the connector body. Second locking surface 140 facing base ring 132 abuts upset core pin 204 for forming a retainer with the compressive members having an inner diameter approximately as large as the diameter of the intersection of the chamfer with the limit surface. The mold core pin 204 is located in the radial center-line or the core of the mold dies 202. The mold core pin 204 has a first cylindrical portion 206, an enlarged cylindrical portion 208 and a conical portion 210 located between the first cylindrical portion 206 and the enlarged cylindrical portion 208.

The set 200 of mold dies and mold core pin defines a cavity 212 for forming the base ring 132, cavities 214 for forming the compressive members 136 and cavities (not shown) for forming the remainder of the resultant retainer 130. The cavity for forming the base ring 132 has an annular surface 216 for forming the limit surface 148 of the base ring 132. The annular surface 216 is axially in-line with the intersection of the enlarged cylindrical portion 208 and the conical portion 210 of the mold core pin 204.

FIG. 9 illustrates a sectional view of the set of mold dies and mold core pin after injection of plastic material into the cavities defined in the set of mold dies and mold core pin. The annular surface 216 of the mold dies 202 forms the limit surface 148 of the base ring 132. The first cylindrical portion 206 of the mold core pin 204 forms the cylindrical surface 146 of the base ring 132. The conical portion 210 of the mold core pin 204 forms the chamfer 150 of the base ring 132. The enlarged cylindrical portion 208 of the mold core pin 204 forms the inner surfaces of the compressive members 136. Upon the injected plastic material solidifying sufficiently, the mold core pin 208 in removed axially outward along the radial center-line in the direction of arrow 218 as illustrated in FIG. 10. Thereafter, the mold dies 202 are removed from the resultant retainer 130 in the direction of arrows 220, 222 and 224 as illustrated in FIG. 11. Since the intersection of the chamfer 150 with the limit surface 148 of the resultant retainer 130 is defined by the intersection of the conical portion 210 of the mold core pin 204 with the enlarged cylindrical portion 208 of the mold core pin 204 and the inner surfaces of the compressive members 136 are defined by the enlarged cylindrical portion 208 of the mold core pin 204, the resultant retainer 130 has compressive members 136 with an inner diameter approximately as large as the diameter of the intersection of the chamfer 150 with the limit surface 148.

FIG. 12 illustrates the sectional view of an alternative set 250 of mold dies 252 and mold core pin 254 for forming a retainer 256 with compressive members 258 having an inner diameter larger than the diameter of the intersection of the chamfer 260 with the limit surface 262 of a base ring 259. The mold core pin 254 of the alternative set 250 of mold dies and mold core pin has an enlarged cylindrical portion 266 having a proportionately larger diameter than the diameter of the enlarged cylindrical portion 208 of the core pin 204 disclosed in the previously disclosed set 200 of mold dies and mold core pin. With the enlarged cylindrical portion 266 having a proportionately larger diameter, the conical portion 268 likewise is proportionately longer axially. Therefore, the intersection of the enlarged cylindrical portion 266 and the conical portion 268 of the mold core pin 254 is not axially in-line with annular surface 270 of mold dies 252 as in the previously disclosed set 200 of mold dies and mold core pin. Rather, the intersection of the enlarged cylindrical portion 266 and the conical portion 268 of the mold core pin 254 is axially outward of the annular surface 270 of the mold dies 252. As the result, the compressive members 258 of the resultant retainer 256 have an inner diameter larger than the diameter of the intersection of the chamfer 260 with the limit surface 262.

FIG. 7 depicts another embodiment of the present invention. Retainer 160 again includes a base ring 162 and compressive members 164. Chamfer 166 is formed between cylindrical wall 168 and perpendicular limit wall 170 during the injection molding process through use of an enlarged diameter core pin as described above. Chamfer 166 is formed at a reduced angle relative to wall 168, as compared to the embodiment of FIG. 6. Portions 172 of compressive members 164 are also removed through use of the core pin. As can be seen, the relatively exotic upset 174 would cause interference within retainer 160 without application of the principles of the present invention.

Various features of the present invention have been explained with reference to the embodiments shown and described. Of course, modification may be made to the described embodiments without departing from the spirit and scope of the invention as represented by the following claims. 

What is claimed is:
 1. A connector to receive a tube end having at least one radially enlarged upset comprising: a hollow female connector body; a retainer disposed in said connector body, said retainer having an annular inner base ring and defining a cylindrical surface to receive the tube end, and said retainer further defining compressive members; said base ring having a limit surface facing said compressive members and a chamfer intersecting said limit surface and said cylindrical surface; said compressive members defining an inner surface and a locking surface intersecting said inner surface, and further defining a space between said limit surface and said compressive members for securing the radially enlarged upset in said connector body; wherein the diameter of the intersection of said locking surface with said inner surface of said compressive members being greater than the diameter of the intersection of said chamfer with said limit surface.
 2. A connector as claimed in claim 1 wherein said chamfer provides tolerance for a wide band of male tube dimensions.
 3. A connector as claimed in claim 1 wherein said inner surface of said compressive members provides tolerance for a wide band of male tube dimensions.
 4. A connector as claimed in claim 1 wherein said chamfer is adapted to accommodate a sloping wall portion of the upset. 